I'm an ophthalmologist and I seem to have more patients with contact lens "irritation", redness, blurred vision with the silicone hydrogels. I would tend to think about overwear and abuse, however, I've had the same experience with my own eyes. Coincidence? Reality? Doesn't seem logical.

While the majority of patients seem to do well with silicone hydrogel lenses, there are some who report discomfort, redness and poor vision with SOME types of these lenses. Fortunately we have 5 currently marketed lens types available now and there will be more very soon, providing more choice.
 
The Acuvue Advance and Acuvue Oasys lenses are not surface treated but contain an internal re-wetting agent (higher levels in the Oasys lens). They are also of different water contents (higher water content in the Oasys lens). The surfaces of O2 Optix and Night & Day are permanently modified in a gas plasma reactive chamber to create a permanent, ultrathin, continuous hydrophilic surface. These lenses differ in their water content, with O2 Optix having a slightly higher water content. Purevision lenses are surface treated in a gas plasma reactive chamber which transforms the silicone components on the surface of the lenses into hydrophilic silicate compounds. These surface treatments and water contents and the modulus (or stiffness) of the lenses can result in different performance for different patients.

We therefore recommend that you try one of the alternative "types" of silicone hydrogel lenses to see if you have more favorable results.